Sterilizing process



Feb. 9, 1937.

STERILIZING PROCESS Filed July 413, 1932 A. Y. oDGE 2,069,820

Patented Feb. 9s, 19.37,.. i

UNITED STATES PATENT OFFICE STERILIZING PROCESS y Adiel Y. Dodge, South Bend, Ind. Application July l, 1932, Serial No. 622,232

4 Claims. (Cl. 99-219) My invention relates to a process of steriliza- CO2 so that it may act on the liquid while it is tion and more particularly to a process of sterilizunder pressure. ing liquids or other fluids mechanically. Other objects and advantages will be apparent It has been found that germs or bacteria can from the following detailed description and from 5 be killed or at least rendered inactive by varying the accompanying drawing illustrating a machine 5 the pressure thereon, as by applying a high presfor carrying out the novel process and in which: sure thereto and then releasing the pressure.J Fig. 1 is a diagrammatic elevation in section of This principle has been utilized to some extent one form of novel apparatus for treating iluids; but as heretofore practiced has been relatively. Fig. 2 is a diagram showing one form of valve expensive due to the large amount of energy reactuating means for the apparatus shown in 10 quired to carry it out successfully. It is accord- Fig. 1;\and ingly one of the objects of the present invention Fig. 3 is a diagram of the timing of thexcycle to provide a process of sterilization which does not of operations. require the expenditure of a 'large amount of In general, germs and bacteria can be brought energy. to an inactive state by subjecting the media in 15 Another object of the invention is to provide which they exist t0 a very high pressure. In a continuous sterilization process. some cases, the sterilization by pressure is ren- The process may be carried out by conning a dered more effective by thel simultaneous use of an body of fluid or liquid to be treated in a cylinder electric current passed through the fluid, or by and forcing apiston or plunger into the cylinder introducing into the illlid t0 be Compressed a 20 to apply a high pressure to the fluid. While the gaseous chemical reagent such as CO2 gas. uid is still confined, pressure upon the'plunger When dealing with liquids and semi-liquids, the may be released whereupon any energy imparted fluids may be brought to a high state of compresto the uid in the form of work done upon it dursion comparatively suddenly by a high pressure ing compression will be returned to the plunger Dump. The highly Compressed llid may be val- 25 and may be stored in a flywheel pending the next lowed to escape threllgh a Very narrOW slit 0r pressure stroke of the piston or may be utilized in valve opening at Very high VelOeitieS, thus allOW- any other desired manner. In this way substaning the Statie Pressure t0 drOp rapidly. One Way tiauy an of the energy imparted to the nuid is of accomplishing this is by a spring closed valve.

recovered therefrom. The rapid velocity change, and the rapid pressure 30 morder to regulate the pressure to which the change both have their good eiect toward deeniluid is subjected, it is preferably conned in a ergiZing the bacteria and the germs.

cylinder which is connected to a spring pressed This method, hOWeVer, aS heretofore practiced plunger adapted to yield when the fluid `reaches a. is very extravagant 0f energy, since the potential '35 predetermined pressure. In-,this way any energy energy iS Converted inte dynamic energy and 10St- 36 absorbed by the spring during the pressure stroke Therefore, I propose that the iluid be subjected will be returned to the plunger during the expant0 a high PIeSS `e against a yielding member Such sien stroke and an accurate regulation of the as --a spring l0 ded piston as shownv in Fig. 4 1. pressure will be obtained without the loss of any UDOD the return Stroke -Of the COlnPreSSOr the appreciable amount; f energy, spring or yielding member will return the energy 40 Fluid to be treated is preferamy supplied to the Stored in it t0 the compression piston duringV the cylinder under pressure and is controlled by inlet Outstroke 0f the PStOn- The energy stored in the and exhaust valves on the cylinder. These valves fluid during the in'stroke of thecompressor Pis' remain closed to conne the uid in the cylinder ton (all fluids are slightly compressible) will also during substantially the entire pressure and rebe returned on the out-stroke of the compressor s tractile strokes of theI plunger and are opened piston to the fly Wheel of the power sul`ce- BY h' me h simultaneously upon completion of each operating t oriedtl gclosrggrgly 105g er may cycle so that a fresh charge of untreated fluid be ued I have Worked out a c c1 e wherein th may force the treated charge from the cylinder. compression chamber is ned bsx', a pump whg 50 If desired the valves may be timed to produce a the compression piston is near its out positmn pressure lower than the feed pressure at theend and en its Way inward, when the chamber 1g of the retractilestrkefull the valves close and the compression plunger Afurtherfeature relates to supplying to a liquid s enters and compresses the duid and the main 55 to be treated, a gaseous chemical reagent such as spring. During theout-stroke the fluid and the 55 spring return most ofthe power to the source. When the compression piston is back the valves are opened and the 4 supply pump pushes the treated fluid out-` and fills the chamber with a new charge to be treated. To insure complete treatment, the new charge may be a little less than the actual capacity of the compression chamber, lius having an overlap, i. e., some 'iluid is 4treated ce. `Referrin to the drawing in detail, the construction ustrated in Fig; l is a single cylinder compressor but can be constructed to be a multiple cylinder compressor. The compression chamber 5 may be a straight bore in which plunger 6 is caused to reciprocate by .any suitable power means through a crank or an eccentric 1. The eccentric maybe surrounded by a ball bearing to reduce friction.- A box yoke 8 is provided as part of the mechanism used t o convert rotary motion into reciprocating motion and is attached to the plunger 6. `As a guide for the box yoke 8, rod 9 is provided but other forms of guide might. well -be used. Part I is an auxiliary plunger closely tting the bore of the compression chamber but free to reciprocate therein. Spring II normally holds the auxiliary plunger I0 into the .compression chamber 5. The spring II abuts Part 33 shows a portion of the intake pipe provided with an auxiliary injection nozzle 31 and pipe 38. This pipe and nozzle are for the purpose'of injecting into the fluid a gaseous chemical reagent, s uch as CO2 gas, air or the like which have been found to be very helpi'ul in sterilizing fluids by compression. This gas injection feature may be omitted entirely in some cases and in others its use is optional even though the parts are retained.

Part 38 is a terminal connection for anelectric wire 39, electric wire 42 being the other wirel necessary for a circuit. Wire 42 feeds -through terminal M into electrode 43. Electrode 43 is surrounded with insulation material 40 as is terminal 44 surrounded with insulation material 4I. In this way auxiliary plunger I0 contains an electrode within itself. By means of this elec trode and the wire 39 fastened to the cylinder casting a current of electricity 'may 'be sent This current Y mostl of the fluid which has been treated, through valve I6. The valves close whenayolume of through theufluid in chamber 5. maypass continuously through the-uid found in chamber 5- or it may be interrupted and caused to pass only at the desired interval. Thus the iluid may be treated with gas and electricity in addition to alternate compression end expansion.

Fig. 3 is diagram showing the timing. Axis X-Y represents the axis along which the piston 8 moves. The circular path .of the crank pin or eccentric is divided into the periods A, B, C. and D. During period A chamber 3 is being illled and both valves are open; during period B luid inv chamber Bis being compressed and both valves are closed; during period C piston 6 ris moving out and recoil from spring II and the' fluid is being transferred back to power source and both valves are closed; and, during period D piston 6 is movv 'a aoeasao pression chamber through the ports Il-and I4 by opening the valves I3 and I1." Fluid is forced into the compression chamber through valve I1 by some suitable pressure means,such as a supply pump or a circulating pump (not shown). The incoming uid to be treated pushes the fluid which has been treated from chamber I out through valve I6.

The valves are timed to be mechanically opened i during the interval A when the plunger 3 is near its outer extremity. .The flow by Va metering valve or the like so that during' the inl terval A of valve opening Just suillcient-uid, to

be treated, enters the chamber 3 to nearly ll it and force out most ofthe uid which has just been treated. By regulating this ilow so that only 80% to 90% of the quantity needed to refill chamber lis forced in, there is only a like amount lforced out, thus leaving a remaining quantity of treated fluid in the chamber 3.1 This overlap insures a thorough treatment of al1 the uid passing through my process. Valves I3 and I1 are opened and closed at the same time by any suitable mechanical means 'such as vshown in Fig. 2. Arms 3Il and 3I are attached to valves I3 and I1. The arms are connected by suitable linkage to the power shaft and caused to rock at the correct intervals to open the valves I6 and I-1 when the'r plunger 6 is near its outer extremity. With this arrangement when a feed pump is used to nil the compression chamber the displacement oi' the compression plunger need be only a small portion of the volume of the chamber, thus saving energy over and above, a practice of using a high pressure plunger to displace substantially all of the volume of its chamber. l

In operation, fluid is forced into the compression chamber, during interval A the valves are closed, the plunger further enters during interval B andcompresses the iluid (to a degree necessary to accomplish the desired results. which may be as high as 10.000 lbs. per sq. in. or more, in

some cases). The spring-II yields to the load and absorbs the force of the com stroke B, but returns the force during the out-stroke C otplunger 6 at which time the spring II forces plunger I0 into the chamber I. thus 'forcing plunger 8 out and returning the force vtothe driving shaft I9 throughcam 1, etc. Dining this time any energy absorbed by the fluid during the compression stroke will also be returned tothe plunger 3. During interval D piston l is drawn further out creating a sub-atmospheric pressure vin the iluid and following this interval the valves arevopened. During interval -A more iiuid is forced in through valve I1 thus pushing out fluid, somewhat less in quantity than. the volume of chamber'l, has passed Pvalve I1. The plunger 6 enters and the cycle is repeated again and again with or without electrlfying the fluid as the needswarrant. Gas maybe introduced through nozzle 31 when needed to deenergize spores.

By using a three or more cylinder compressor the valves and plungers may be ltimed so that' practically a continuous ow of iluid'such as water, milk, fruit juices or the like can be treated with pressure which quickly alternates from low to high pressure 'and .back to lower pressure., In

some cases, it may be desirable to treat the uid witha repeated compression stroke. l This can be aoeasao stroke. This is accomplished by introducing a reduction gear (not shown) between drive shaft i9 and the shaft which drives the linkage for moving arms 30 and 3l.

While I have shown certain simple forms of my applying a compressive force to the iluid, relieving the compressive force, reducing the pressure on said iluid to less than atmospheric and forcing a. new charge of iluid into the chamber to force out the treated charge.

2. The process of sterilizing iluid which comprises forcing a charge of uid into a chamber, applying a compressive force to the fluid by a compressive member, relieving the pressure on the fluid while maintaining it conilned whereby the energy absorbed by the fluid during compression will be returned to the compressive member and forcing a new charge of fluid into the chamber to torce out the treated charge.

3. The process o! sterilizing iluid which comprises forcing a charge of uid into a chamber, applying a compressive force to the uid by means of a compressive member, limiting the pressure on said iiuid by absorbing excess pressure in energy absorbing means, relieving the pressure on said uid while keeping it conned whereby the energy absorbed by the iluid and energy absorbing means during compression will be returned to the compressive member and forcing a new charge of fluid into the chamber to force out the treated charge.

4. The process of sterilizing uid which comprises forcing a charge of uid into a chamber, applying a compressive force to the iuid by means of a compressive member, limiting the pressure on said uid by absorbing excess .pressure in energy] absorbing means, relieving the pressure on said fluid while keeping it confined whereby the energy absorbed by the uid and energy absorbing means during compression will be re.

turned to the compressive member, reducing the pressure on said fluid to less than atmospheric and forcing a new charge of iluid into the chamber to force out the treated charge.

ADIEL Y. DODGE. 

